As a society we want polymeric materials with a variety of desirable physical properties in our rooms, housing, vehicles, shopping centers, offices, factories, restaurants, theaters, sports complexes, etc. In most of these applications we would also like a certain degree of fire retardancy so that in the event of a fire, any occupants or visitors could safely exit the structure before they are overcome by smoke, heat, carbon monoxide or dioxide, etc.
As a society we would also like the manufacturing, recycling, and disposal of the construction materials used in the above structures to not unduly contaminate the environment. Halogenated flame retardant compounds (while used extensively in the past) represent some hazards to society in terms of contamination of the environment by manufacturing and disposal. They can also generate of acidic fumes in the event of a fire. Flame retardants based on phosphoric acid and amine compounds are similar to biological molecules in animals and plants. Some phosphoric acid species and amine species could be biodegraded back into nutrients for plants or animals. Phosphoric acid species and amine species also tend to generate less overwhelming fumes than halogenated flame retardants.
Guanylurea salts of phosphoric acid species as particulates have been used in the past as a somewhat inorganic flame retardant material for cellulosic products and some polymers. However, the water solubility of guanylurea and phosphoric acid species always generates some concern that flame retardant properties will be lost by washing or leaching with polar or water based solutions. It would be desirable if guanylurea and phosphoric acid migration from construction materials could be slowed down or prevented in the event of exposure to water or polar solvents.
GB1453296 teaches a flameproofing organic fibre material and a preparation for use therein. It includes phosphonium compounds and amine compounds such as dicyanadiamide cyanourea, and guanylurea.
U.S. Pat. No. 6,652,633 teaches a Fire Retardant that includes guanylurea phosphate and boric acid along with materials such as wood and composite wood products.
U.S. 2003/0083393A1 teaches a method for producing a rigid polyurethane foam using a polyol a polyisocyanate in the presence of an amine catalyst and a blowing agent.
U.S. 2013/220170 teaches flame retardant compositions for cotton articles using tetrakishydoxyalkyphonhonium salt with caprolactam and urea.